In an E-mail message, DUNN  JEREMY SIMON wrote:
> 
> GoodAfternoon, 
> 
> I'm interested in getting a 50km grid overlay on a map of the Mississippi River
> Basin I have. Is there a way of creating this in Grass ?
> 
> Thanks 

Jerry,

I believe you can use the Grass program v.mkgrid to accompish what you want.
Here's part of the man page:

NAME
     v.mkgrid - Creates a (binary) GRASS vector map of a user-
     defined grid.
     (GRASS Vector Program)

SYNOPSIS
     v.mkgrid
     v.mkgrid help
     v.mkgrid map=name grid=rows,columns coordinate=x,y
     box=length,width

DESCRIPTION
     v.mkgrid will create a binary format, vector map
     representation of a regular coordinate grid.

     Parameters:

     map=name                Name to be assigned to binary vector
                             map layer output.

     grid=rows,columns       Number of ROWS and COLUMNS to appear
                             in grid.

     coordinate=x,y          Lower left EASTING and NORTHING
                             coordinates of vector map layer
                             output.

     box=length,width        LENGTH and WIDTH of boxes in grid.

     If the user simply types v.mkgrid on the command line
     without specifying parameter values, the program will prompt
     the user for inputs using the standard interface described
     in the manual entry for parser.

NOTES
     The new binary vector map output is placed under the dig
     directory in the user's current mapset, and can be used like
     any vector map layer.  Run v.support to build the topology
     information for the vector map before using v.mkgrid map
     layer outputs in the v.digit program.


-- 
-------------------------

Paul Loechl					p-loechl@cecer.army.mil
USA CERL					(217)352-6511x7668

